Seed morphology in the genus Iris (Iridaceae) from Russia

The genus Iris in Russia is represented by 41 species. Four species are endemic, 11 are included in the Red Data Book of the Russian Federation and 30 have different regional conservation status. The presented results of the study of the morphology of seeds and of seed coat surface morphology in 40 species from the genus Iris growing in Russia were obtained mainly using light and scanning electron microscopy. Seed shape is round, ovate, oblong or pear‑shaped, with the exception for I. psammocola, in which it is club‑shaped. The smallest seeds in the studied species belong to I. ruthenica and I. uniflora. Morphometric data lead to interesting conclusions regarding the taxonomic relations between some species. For example, the species currently considered as synonyms, e.g., I. biglumis and I. pallasii in I. lactea, and I. maackii in I. pseudacorus, are found different concerning seed morphology. On the other hand, the taxonomically well distinct species such as I. halophila and I. pseudonotha share similar seed morphology. A study of the morphological characteristics of the seed coat surface in 40 species of the genus Iris made it possible to compile an atlas for determining species in the genus Iris in Russia.